Stains that are not visible to the eye are often present on many types of surfaces. Detection of such stains, without affecting the surface, is an important process, especially in museums, forensic labs, textile industries, etc. Such stains can sometimes be located through the use of an ultraviolet light source (e.g., a black light) that emits light having a wavelength within a range 10 nm to 400 nm, depending on the composition and concentration of the stain and/or the surface.
However, not all stains are visible using detection currently known techniques. A need exists for detection of a latent stain on a surface when the nature of the stain composition and/or its concentration (e.g., relatively small) inhibits detection from other methods.